The proposed studies represent continuation of a long-term program on the biochemistry of the male genital tracts of mammals with special emphasis on the mechanisms and hormonal control of molecular processes related to the functions of the testis and male genital glands. Further experiments will be conducted on the fractionation, structure and functions of bulk proteins in vesicular gland secretions. Multiple forms of transglutaminases from the anterior prostate will be purified and characterized with respect to catalysis of both the cross linking of vesicular secretion proteins and the covalent incorporation of polyamines into the latter and other protein acceptor substrates. The physiological significance of post-translational modification of proteins via the formation of covalently attached polyamine adducts will be evaluated. Other investigations will relate to the enzymology, and endocrine and drug regulation, of the formation and turnover of (a) polyamines, and (b) organ-specific proteins in the testis and various male accessory glands.